Ok. So I finally got out to the range to shoot my rifle and it was awesome, at first. The first 20 rounds functioned flawlessly. The second mag had some problems. The rifle "double-tapped" on me twice. What I mean by that is rifle fired 2 shots very rapidly, so fast in fact that I wasn't sure it happened the first time. It didn't "run away" on me because I had ammo left in the mag after it happened both times. So my question is what do I do?